This invention relates to a fluid switch having three ports and electrical switch means for controlling flow of fluid through said ports. The invention also relates to a valve assembly having electrical means for controlling the fluid pressure relative to a working volume in three control states. The control states may apply, hold or release fluid pressure relative to the working volume.
The fluid switch may be used in connection with any suitable application such as a fluid valve or for applications other than valves, for example pistons.
The valve assembly may be an ABS valve in the brake system of a vehicle in which the control states may apply, hold or release fluid pressure from the working volume which, in this case, comprises a vehicle brake.
Objects of the invention are to provide a new and improved fluid switch and a new and improved valve assembly, and in particular is more economical than an existing valve assembly.